A perception-communication integration method based on delay-Doppler domain signal processing

Abstract

The present application provides a method for integrated perception and communication based on delay-Doppler domain signal processing, which is implemented by a radar end and a target end, and the method includes: step 1: the radar end constructs an ISAC waveform in the delay-Doppler domain according to the position information of the target end obtained by step 4 and the channel parameters in the delay-Doppler domain; step 2: the radar end sends the ISAC waveform in the delay-Doppler domain; step 3: the target end receives the ISAC waveform in the delay-Doppler domain, and performs channel estimation and signal detection in the delay-Doppler domain; step 4: the radar end receives the echo reflected by the target end, locates the target end according to the echo to obtain the position information of the target end, and obtains the channel parameters in the delay-Doppler domain. The present application directly uses the channel information in the delay-Doppler domain obtained by the radar end for the signal design based on the delay-Doppler domain, which reduces the complexity of realizing the integrated perception and communication technology and improves the communication reliability.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a perception-communication integration method based on delay-Doppler domain signal processing. Background Art

[0002] Perception is the detection of parameters of the physical environment, such as speed measurement, target positioning, etc. Communication is the transmission of information between two or more points. The integration of perception and communication refers to the fusion of the two functions of perception and communication. It can communicate with related targets while detecting surrounding targets, thereby reducing network costs and improving positioning accuracy and communication reliability. The integration of perception and communication technology can be applied in wireless communications, intelligent transportation and other related fields.

[0003] The perception and communication integration technology in the prior art uses the transmission and reflection of communication signals based on time-frequency domain modulation to achieve perception and communication; communication signals based on time-frequency domain modulation, such as OFDM signals. However, the perception and communication integration technology based on communication signals modulated in the time-frequency domain requires a more complex channel estimation algorithm to receive and process communication signals. At the same time, due to the characteristics of the time-frequency domain channel, the communication signals based on time-frequency domain modulation need to frequently update channel information, thereby increasing the complexity of signal reception and processing and further resulting in low efficiency of perception communication. Summary of the invention

[0004] In view of this, the purpose of this application is to propose a perception-communication integration method based on delay-Doppler domain signal processing.

[0005] Based on the above purpose, the present application provides a perception communication integration method based on delay Doppler domain signal processing, which is implemented by a radar end and a target end, and the method includes:

[0006] Step 1: The radar end constructs an ISAC waveform in the delay-Doppler domain according to the position information of the target end obtained in step 4 and the channel parameters in the delay-Doppler domain;

[0007] Step 2: The radar terminal sends the ISAC waveform in the delay-Doppler domain;

[0008] Step 3: The target end receives the ISAC waveform in the delay-Doppler domain, and performs channel estimation and signal detection in the delay-Doppler domain;

[0009] Step 4: The radar end receives the echo reflected by the target end, locates the target end according to the echo to obtain the position information of the target end, and obtains the channel parameters in the delay Doppler domain.

[0010] From the above, it can be seen that the perception communication integration method based on delay-Doppler domain signal processing provided by the present application is implemented through the radar end and the target end, and the method includes: step 1: the radar end constructs the ISAC waveform in the delay-Doppler domain according to the position information of the target end obtained through step 4 and the channel parameters in the delay-Doppler domain; step 2: the radar end sends the ISAC waveform in the delay-Doppler domain; step 3: the target end receives the ISAC waveform in the delay-Doppler domain, and performs channel estimation and signal detection in the delay-Doppler domain; step 4: the radar end receives the echo reflected by the target end, locates the target end according to the echo to obtain the position information of the target end, and obtains the channel parameters in the delay-Doppler domain. The present application directly uses the channel information in the delay-Doppler domain obtained by the radar end for the signal design based on the delay-Doppler domain, which reduces the complexity of realizing the perception communication integration technology and improves the communication reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the present application or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0012] Figure 1 A flow chart of a method for integrating perception and communication based on delay-Doppler domain signal processing provided in an embodiment of the present application;

[0013] Figure 2 A schematic diagram of a scenario of interaction between a radar end and a target end provided according to an embodiment of the present application;

[0014] Figure 3 A schematic diagram of a flow chart of a method for constructing an ISAC waveform in the delay-Doppler domain according to an embodiment of the present application;

[0015] Figure 4 A flowchart of a method for constructing a sending signal provided according to an embodiment of the present application is provided. DETAILED DESCRIPTION

[0016] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0017] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0018] As described in the background technology section, the integrated perceptual communication technology implemented based on communication signals modulated in the time-frequency domain requires a more complex channel estimation algorithm to receive and process communication signals. At the same time, due to the characteristics of the time-frequency domain channel, the communication signal based on time-frequency domain modulation needs to frequently update channel information, which increases the complexity of signal reception and processing and further leads to low efficiency of perceptual communication.

[0019] In view of this, the present application proposes a perception-communication integration method based on delay-Doppler domain signal processing.

[0020] refer to Figure 1 , which is a flow chart of a method for integrating perception and communication based on delay-Doppler domain signal processing provided in an embodiment of the present application;

[0021] The perception and communication integration method based on delay-Doppler domain signal processing includes:

[0022] S110, the radar end constructs an ISAC waveform in the delay-Doppler domain according to the position information of the target end obtained in S140 and the channel parameters in the delay-Doppler domain.

[0023] ISAC (Intergrated Sensing and Communication): ISAC waveform is the intergrated sensing and communication waveform.

[0024] In some implementation scenarios, the radar sends an ISAC waveform in the delay-Doppler domain, receives an echo reflected by the target, then sends an ISAC waveform in the delay-Doppler domain, then receives an echo reflected by the target, and so on, and repeats the above operations. Except for the ISAC waveform in the delay-Doppler domain sent by the radar for the first time, which is constructed by initialization, the ISAC waveform in the delay-Doppler domain sent by the radar is constructed based on the echo reflected by the received target.

[0025] The radar locates the target according to the echo reflected by the target, obtains the position information of the target, and obtains the channel parameters in the delay Doppler domain.

[0026] In some embodiments, the location information of the target terminal includes:

[0027] The relative angle and relative distance between the target end and the radar end.

[0028] In some embodiments, the channel parameters in the delay-Doppler domain include:

[0029] Relative Doppler shift.

[0030] Doppler shift refers to the change in phase and frequency caused by the difference in propagation distance when a mobile station moves in a certain direction at a constant speed. It reveals the law that the properties of waves change during movement. When moving in front of the wave source, the wave is compressed, the wavelength becomes shorter, and the frequency becomes higher; when moving behind the wave source, the opposite effect occurs, the wavelength becomes longer, and the frequency becomes lower.

[0031] S120: The radar sends the ISAC waveform in the delay-Doppler domain.

[0032] There is at least one target end within the signal coverage range of the radar end. As an example, the radar end is provided with N T Antennas are used to send signals, and each target end is equipped with N R An antenna is used to receive signals.

[0033] The radar sends different delay-Doppler domain ISAC waveforms to different targets.

[0034] refer to Figure 2 There are three target ends within the signal coverage of the radar end. The radar end sends the ISAC waveform in the delay Doppler domain respectively, receives the echo reflected by the target end, and then sends the ISAC waveform in the delay Doppler domain respectively, and then receives the echo reflected by the target end..., and repeats the above operation repeatedly.

[0035] S130: The target end receives the ISAC waveform in the delay-Doppler domain, and performs channel estimation and signal detection in the delay-Doppler domain.

[0036] In some embodiments, the target end receives the ISAC waveform in the delay-Doppler domain and performs channel estimation and signal detection in the delay-Doppler domain, including:

[0037] Estimate the channel fading parameters at the radar end.

[0038] In some embodiments, estimating a channel fading parameter at a radar end includes:

[0039]

[0040] in, is the channel fading parameter; c is the speed of light; f c is the carrier frequency; d k is the relative distance.

[0041] The transmit power at the radar end is calculated based on the channel fading parameters.

[0042] In some embodiments, calculating the transmit power of the radar end according to the channel fading parameter includes:

[0043]

[0044] Among them, P k is the transmit power.

[0045] The received signal at the target end is calculated according to the transmission power, and the received signal is detected to obtain a transmission symbol sequence.

[0046] In some embodiments, calculating a received signal received by a target end according to the transmit power includes:

[0047]

[0048] Among them, y k [n,m] is the received signal; x k [n,m] is the transmission symbol sequence corresponding to the kth target end; w[n,m] is the Gaussian white noise sampling point.

[0049] In some embodiments, performing signal detection on a received signal to obtain a transmission symbol sequence includes:

[0050]

[0051] Among them, x k [n,m] is the transmission symbol sequence corresponding to the kth target end; is the set of constellation points corresponding to the transmission symbol sequence.

[0052] S140, the radar end receives the echo reflected by the target end, locates the target end according to the echo to obtain the position information of the target end, and obtains the channel parameters in the delay Doppler domain.

[0053] In some embodiments, according to the radar signal processing method in the related art, it is possible to locate the target end according to the echo to obtain the position information of the target end and obtain the channel parameters in the delay Doppler domain. The present application has not made any improvement on this.

[0054] refer to Figure 3 , which is a flow chart of a method for constructing an ISAC waveform in the delay-Doppler domain provided in an embodiment of the present application.

[0055] In some embodiments, the radar end constructs an ISAC waveform in the delay-Doppler domain according to the position information of the target end obtained in S140 and the channel parameters in the delay-Doppler domain, including:

[0056] S210: Construct at least one sending signal.

[0057] refer to Figure 4 , which is a flow chart of a method for constructing a sending signal provided according to an embodiment of the present application.

[0058] In some embodiments, constructing a transmission signal comprises:

[0059] S310, obtaining a transmission symbol sequence corresponding to the target end.

[0060] The transmitted symbol sequence is the substantial information content of the ISAC waveform in the delay-Doppler domain.

[0061] The transmission symbol sequence corresponding to the kth target end is expressed as x k , 1≤k≤K, K is the number of target ends, and the sent signal may be different for different target ends.

[0062] S320: Construct a time-frequency domain transmission symbol corresponding to the target end according to the transmission symbol sequence.

[0063] Specifically include:

[0064]

[0065] Among them, X k [n,m] is the time-frequency domain transmission symbol corresponding to the kth target end; M is the number of subcarriers; N is the number of subsymbols; x k[n',m'] is the transmission symbol sequence corresponding to the kth target end; e is a natural constant; j is an imaginary number; Δf is the subcarrier spacing; t is a time variable; T is the subsymbol duration; n is the time domain symbol index, m is the frequency domain symbol index, n' is the Doppler domain symbol index; m' is the delay domain symbol index;

[0066] S330: Construct a transmission signal according to the time-frequency domain transmission symbols.

[0067] Specifically include:

[0068]

[0069] Among them, s k (t) is the sending signal corresponding to the kth target end; g tx (t-nT) is the waveform shaped at the sending end.

[0070] In some embodiments, the signal transmission object of the radar end is multiple target ends, that is, it is necessary to construct a corresponding transmission signal for each target end.

[0071] Assuming there are K target terminals, the set of transmitted signals consisting of K transmitted signals is:

[0072] s(t)=[s1(t),s2(t),...,s K (t)] T .

[0073] in,[……] T Represents a transpose operation.

[0074] S220: construct a beamforming matrix according to the relative Doppler frequency shift and the relative angle between the target end and the radar end.

[0075] The beamforming matrix is ​​denoted as F and its size is N T ×K. Among them, N T is the number of antennas set on the radar end for sending signals, and K is the number of target ends.

[0076] In the beamforming matrix F, the vector of the kth column is

[0077] Among them, P k is the transmission power; e is a natural constant; j is an imaginary number; is the relative Doppler frequency shift, t is the time variable; is the guidance vector corresponding to the kth target end.

[0078] in,

[0079] in, is a relative angle.

[0080] S230: construct an ISAC waveform in the delay-Doppler domain according to the transmitted signal and the beamforming matrix.

[0081]

[0082] in, is the ISAC waveform in the delay-Doppler domain; F is the beamforming matrix; s(t) is the set of transmitted signals.

[0083] From the above, it can be seen that the perception communication integration method based on delay-Doppler domain signal processing provided by the present application is implemented through the radar end and the target end, and the method includes: step 1: the radar end constructs the ISAC waveform in the delay-Doppler domain according to the position information of the target end obtained through step 4 and the channel parameters in the delay-Doppler domain; step 2: the radar end sends the ISAC waveform in the delay-Doppler domain; step 3: the target end receives the ISAC waveform in the delay-Doppler domain, and performs channel estimation and signal detection in the delay-Doppler domain; step 4: the radar end receives the echo reflected by the target end, locates the target end according to the echo to obtain the position information of the target end, and obtains the channel parameters in the delay-Doppler domain. The present application directly uses the channel information in the delay-Doppler domain obtained by the radar end for the signal design based on the delay-Doppler domain, which reduces the complexity of realizing the perception communication integration technology and improves the communication reliability.

[0084] Specifically, radar perception information contains relevant information in the target delay Doppler domain. Radar perception information in related technologies needs to be calculated to infer channel information in the time-frequency domain for signal design. This part of the calculation often brings additional calculations and requires higher implementation complexity. This application directly applies this information to signal design based on time-frequency domain modulation, so this application effectively reduces the complexity.

[0085] The ISAC signal designed based on the time-frequency domain in the related art cannot directly use the channel information in the delay-Doppler domain. Compared with the channel parameters in the delay-Doppler domain, the channel state in the time-frequency domain changes faster. Therefore, the perception-communication integrated network in the related art needs to frequently apply radar to obtain the perception information of the target to estimate the channel parameters, which makes the system inefficient and has a large overhead. The present application designs the ISAC signal from the delay-Doppler domain. Since the channel parameters in the delay-Doppler domain are more stable than those in the time-frequency domain, it is not necessary to estimate the channel parameters frequently, thereby improving the system efficiency and reducing the required overhead.

[0086] Compared with the channel parameters in the delay-Doppler domain, the channel parameters in the time-frequency domain in the related art are often more dense, that is, the channels at different times and frequencies are different, so the complexity of precoding and detection is high when the ISAC signal is sent and received, and the reliability of communication is low. The present application designs the ISAC signal from the delay-Doppler domain. Since the channel parameters in the delay-Doppler domain have the sparse characteristics, compared with the signals modulated in the time-frequency domain, the complexity of the transmitting end precoding and the receiving end detection required by the present application is lower, and since the delay-Doppler domain modulated signal has the characteristics of time-frequency domain expansion, its communication reliability is higher than that of the time-frequency domain modulated signal.

[0087] It should be noted that the method of the embodiment of the present application can be performed by a single device, such as a computer or server. The method of this embodiment can also be applied to a distributed scenario and completed by multiple devices cooperating with each other. In the case of such a distributed scenario, one of the multiple devices can only perform one or more steps in the method of the embodiment of the present application, and the multiple devices will interact with each other to complete the described method.

[0088] In the perception and communication integrated system in the related art, the design of ISAC signals is usually based on the time-frequency domain design. The present application fully considers the signal design method in the delay-Doppler domain, and combines the channel parameters in the delay-Doppler domain obtained by radar perception with the signal design, thereby improving the reliability of communication. At the same time, since the radar can directly obtain the channel information in the delay-Doppler domain, there is no need to convert it to the time-frequency domain for signal design, thereby speeding up the processing speed. On the other hand, considering the characteristics of the delay-Doppler domain channel parameters, the method proposed in the present application can greatly reduce the number of channel estimates, thereby saving costs.

[0089] It should be noted that the above describes some embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0090] It should be noted that the embodiments of the present application can be further described in the following manner:

[0091] A perception and communication integration method based on delay-Doppler domain signal processing, comprising:

[0092] Step 1: The radar constructs the ISAC waveform in the delay-Doppler domain according to the location information of the target end obtained in step 4 and the channel parameters in the delay-Doppler domain;

[0093] Step 2: The radar sends the ISAC waveform in the delay-Doppler domain;

[0094] Step 3: The target end receives the ISAC waveform in the delay-Doppler domain and performs channel estimation and signal detection in the delay-Doppler domain;

[0095] Step 4: The radar receives the echo reflected by the target, locates the target according to the echo, obtains the position information of the target, and obtains the channel parameters in the delay Doppler domain.

[0096] Optional, the location information of the target end, including:

[0097] The relative angle and relative distance between the target end and the radar end.

[0098] Optional, delay-Doppler domain channel parameters, including:

[0099] Relative Doppler shift.

[0100] Optionally, the radar end constructs an ISAC waveform in the delay-Doppler domain according to the position information of the target end obtained in step 4 and the channel parameters in the delay-Doppler domain, including:

[0101] constructing at least one transmit signal;

[0102] According to the relative Doppler frequency shift and the relative angle between the target end and the radar end, a beamforming matrix is ​​constructed;

[0103] The ISAC waveform in the delay-Doppler domain is constructed based on the transmitted signal and the beamforming matrix.

[0104] Optionally, construct at least one sending signal, including:

[0105] Obtain the transmission symbol sequence corresponding to the target end;

[0106] According to the transmission symbol sequence, the time-frequency domain transmission symbol corresponding to the target end is constructed; specifically, it includes:

[0107]

[0108] Among them, X k [n,m] is the time-frequency domain transmission symbol corresponding to the kth target end, 1≤k≤K; M is the number of subcarriers; N is the number of subsymbols; x k[n',m'] is the transmission symbol sequence corresponding to the kth target end; e is a natural constant; j is an imaginary number; Δf is the subcarrier spacing; t is a time variable; T is the subsymbol duration; n is the time domain symbol index, m is the frequency domain symbol index, n' is the Doppler domain symbol index; m' is the delay domain symbol index;

[0109] Construct a transmission signal based on the time-frequency domain transmission symbols; specifically including:

[0110]

[0111] Among them, s k (t) is the sending signal corresponding to the kth target end; g tx (t-nT) is the waveform shaped at the sending end.

[0112] Optionally, a beamforming matrix is ​​constructed according to the relative Doppler frequency shift and the relative angle between the target end and the radar end, including:

[0113] The size of the beamforming matrix is ​​N T ×K;

[0114] In the beamforming matrix, the vector of the kth column is

[0115] Among them, P k is the transmit power; is the relative Doppler shift; is the guidance vector corresponding to the kth target end;

[0116] in,

[0117] in, is a relative angle.

[0118] Optionally, the target end receives the ISAC waveform in the delay-Doppler domain and performs channel estimation and signal detection in the delay-Doppler domain, including:

[0119] Estimate the channel fading parameters at the radar end;

[0120] Calculate the transmit power of the radar end according to the channel fading parameters;

[0121] The received signal at the target end is calculated according to the transmission power, and the received signal is detected to obtain a transmission symbol sequence.

[0122] Optionally, estimate the channel fading parameters at the radar end, including:

[0123]

[0124] in, is the channel fading parameter; c is the speed of light; f c is the carrier frequency; d k is the relative distance.

[0125] Optionally, the transmit power of the radar end is calculated according to the channel fading parameter, including:

[0126]

[0127] Among them, P k is the transmit power.

[0128] Optionally, calculating a received signal received by the target end according to the transmit power includes:

[0129]

[0130] Among them, y k [n,m] is the received signal; w[n,m] is the Gaussian white noise sampling point;

[0131] Performing signal detection on the received signal to obtain a transmission symbol sequence includes:

[0132]

[0133] in, is the set of constellation points corresponding to the transmission symbol sequence.

[0134] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0135] In addition, to simplify the description and discussion, and in order not to make the embodiments of the present application difficult to understand, the known power supply / ground connection with the integrated circuit (IC) chip and other components may or may not be shown in the provided drawings. In addition, the device can be shown in the form of a block diagram to avoid making the embodiments of the present application difficult to understand, and this also takes into account the fact that the details of the implementation of these block diagram devices are highly dependent on the platform to be implemented in the embodiments of the present application (that is, these details should be fully within the scope of understanding of those skilled in the art). In the case of elaborating specific details (e.g., circuits) to describe exemplary embodiments of the present application, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details or when these specific details are changed. Therefore, these descriptions should be considered to be illustrative rather than restrictive.

[0136] Although the present application has been described in conjunction with specific embodiments of the present application, many replacements, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may use the embodiments discussed.

[0137] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A perception and communication integration method based on delay-Doppler domain signal processing, implemented by a radar end and a target end, the method comprising: Step 1: The radar end obtains a transmission symbol sequence corresponding to the target end; According to the transmission symbol sequence, constructing the time-frequency domain transmission symbol corresponding to the target end; specifically comprising: ;in, is the time-frequency domain transmission symbol corresponding to the kth target end, 1≤k≤K; M is the number of subcarriers; N is the number of subsymbols; is the transmission symbol sequence corresponding to the kth target end; e is a natural constant; j is an imaginary number; ∆ f is the subcarrier spacing; t is the time variable; T is the subsymbol duration; n is the time domain symbol index, m is the frequency domain symbol index, n' is the Doppler domain symbol index; m' is the delay domain symbol index; construct a transmission signal according to the time-frequency domain transmission symbol; specifically includes: ;in, is the sending signal corresponding to the kth target end; shaping a waveform for the transmitting end; constructing a beamforming matrix according to the relative Doppler frequency shift and the relative angle between the target end and the radar end; constructing an ISAC waveform in the delay Doppler domain according to the transmitting signal and the beamforming matrix; Step 2: the radar end sends the ISAC waveform in the delay-Doppler domain; wherein the ISAC waveform in the delay-Doppler domain sent by the radar end for the first time is constructed by initialization; Step 3: The target end receives the ISAC waveform in the delay-Doppler domain, and performs channel estimation and signal detection in the delay-Doppler domain; Step 4: The radar end receives the echo reflected by the target end, locates the target end according to the echo to obtain the position information of the target end, and obtains the channel parameters in the delay Doppler domain.

2. The method according to claim 1, wherein: The step of constructing a beamforming matrix according to the relative Doppler frequency shift and the relative angle between the target end and the radar end includes: The size of the beamforming matrix is ; In the beamforming matrix, the vector of the kth column is ; in, is the transmit power; is the relative Doppler shift; is the guidance vector corresponding to the kth target end; in, ; in, is a relative angle.

3. The method according to claim 1, wherein: The target end receives the ISAC waveform in the delay-Doppler domain and performs channel estimation and signal detection in the delay-Doppler domain, including: estimating channel fading parameters of the radar end; Calculating the transmission power of the radar terminal according to the channel fading parameter; A received signal received by the target end is calculated according to the transmission power, and signal detection is performed on the received signal to obtain the transmission symbol sequence.

4. The method according to claim 3, wherein: The estimating the channel fading parameter of the radar end includes: ； in, is the channel fading parameter; c is the speed of light; f c is the carrier frequency; d k is the relative distance.

5. The method according to claim 4, wherein: The calculating the transmission power of the radar end according to the channel fading parameter includes: ； in, is the transmit power.

6. The method according to claim 5, wherein: The calculating the received signal received by the target end according to the transmit power includes: ； in, To receive the signal; is the Gaussian white noise sampling point; The performing signal detection on the received signal to obtain the transmission symbol sequence includes: ； in, is the set of constellation points corresponding to the transmitted symbol sequence.

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